An ambiguous term used to express that a potential hook-up/romantic interest/etc. possesses multiple, unnamed desirable qualities—most commonly material ones (i.e. desirable physical characteristics, wealth or the trappings thereof, etc.)— that the speaker asserts makes the person being spoken about more attractive than other potentials.

"Got" can be seen as trumping "hot" when one is choosing between multiple "hot" possibilities.

It is likely/possible that the usage evolved from the more common "s/he's hot," either from conventional informal phonetic play or even from internet/typo humor (as in teh), as the "g" character is adjacent to the "h" character on keyboards using the standard qwerty layout.

"Yeah, Dewey and them are ok and all, but Don's got and single, you know?"